362 BOTANICAL GAZETTE [November 



* 



It will be observed (fig. 31) that the nuclei with their associated 

 material have assumed a more regular form. The nucleus itself 



in some 



limits of the spore. No indications of cilia have been observed at 



* 



this stage, but they can be seen occasionally in a later stage, that is, 

 at the time of discharge of the zoospores. The condition of the 

 nucleus described strongly suggests that the cilia have their origin 

 through its direct influence. 



Segmentation usually results in the formation of uninucleate 

 zoospores. Occasionally, however, one may find binucleate zoo- 

 spores with the nuclei in the same or different central bodies, or 

 what I shall hereafter call food masses or bodies. Fig. 34 shows 



from 



Fig. 



same 



those in fig. 34. 



In preparation for germination the zoospore comes to rest, takes 



cilium 



comm 



>nly becomes enlarged at the end (fig. 25). The 

 large reserve food body disappears and a large number of variously 

 sized granules take its place. In the course of 10-20 minutes the 

 germ tube makes its appearance and grows rapidly, forming the 

 basis for the subsequently developed rhizoid system (figs. 26, 27, 

 2, a-c). The body of the zoospore forms the basal cell of the plant. 

 Fig. 36 represents a zoospore stained with iron-alum hema- 

 toxylin, preparing to germinate. As described above, the reserve 



apparently broken up into a number of deeply 

 staining granules. As the germ tube elongates, the nucleus 



mass 



form 



•anying 

 more and more vacuolated 



Stained preparations of germinating zoospores beyond the four- 

 nucleate stage were not obtained. 



Just what the nature of the so-called reserve food bodies is has 

 not been determined. Fig. 41 shows a zoospore killed with iodine 

 solution. The nucleus and some granules show distinctly, while 



in most 



Fig. 42, killed with 

 weak Flemming solution, reveals that body clearly, and also the 



